Synthesis of oxochlorins from the red blood pigment heme and their transformation into potentially biologically active chlorin derivatives

Abstract

Abstract The hydroxychlorin rac ‐ 3 was prepared from the readily accessible chlorins rac ‐ 5a, b . The alcohol function of rac ‐ 3 could be used to attach an estrogen residue 28 and the hydroquinone 19 to yield the chlorin estrogen ethers 32a, b and the chlorin hydroquinone ether rac ‐ 30 respectively. The prepared chlorin estrogen derivatives might be useful as sensitizers and fluorescence markers for photodynamic therapy and other diagnostic/therapeutic applications. The chlorin hydroquinone ether is of interest as a potential artificial photosynthesis system, which contains a „natural”︁ chlorin as a structural subunit in contrast to previously synthesized model systems based on porphyrins.